Any one into Generative Design ?

Yes, I agree. We are beating a dead horse, but I am not still sure which horse is dead. Only time will tell. We need to give this time.

I like to thank everyone who participated in this thread for their very valuable views and insights, it has been valuable and engaging. I have learn t a great deal from it.

Yo, you can consider this thread officially closed if you wish.

Cheers

Wait, I think we found the subject of the competition, man vs. machine design.

“Design an object for flogging an expired equine”

Just as soon as you answer the question I asked you.

I think comparing Architecture to Industrial Design is like comparing apples to oranges. We use many of the same tools and techniques, but for very different reasons. At this point in time we may be 5 years behind in accepting these tools, but if you consider that Architecture is an ancient established profession and that Industrial Design (design for mass product if you want to call it) has been around less than 150 years i’d say that ID has a vastly accelerated time line than architecture. We also follow different constraints, if I wanted to design a one-off sofa using generative design tools more power to me, if I want to use them for mass production then the scheme gets much more complicated. I think you miss the point, generative design tools are more advanced than the means manufacturing has to produce many of it’s outcomes.

How come architects haven’t embraced mass production to built homes?

Does a house painter and a portraitist use paintbrushes to reach the same end?

Could this thread finally be making a constructive turn?

Like many, I found the OP really started things off rough (and kept going!?) Can we now discuss and show GD on our terms? GD doesn’t have to be implemented the way he suggested (spit out iterations, recombine, refine). I mean, architects aren’t even using it that way, are they? Why should we?

Sure, someday our immense computing power will give us Matrix-like environments and virtual people evaluating products and interacting with each other etc. It will take (at the very least) that much context for meaningful self-guidance of such a system. Fun to imagine I guess.

Anyway, let’s come back. What are people doing? Architects are saving huge time and money getting GD help with things like all the connections in China’s Bird’s Nest. I get that. If I ever design a large piece of organic shaped furniture, I’d consider it. Looking at Grasshopper Photos - Grasshopper right now. Nice. GD seems to be the thing for visual biomimicry. It could be huge when CNC and rapid proto gets cheaper.

GD will co-evolve with the designers who use them. I found the man vs machine challenge idea hilarious. What was supposed to happen after that apocalyptic showdown? “…And the next day, all the designers in the world had lobotomies to face the reality they were no longer needed… Now software engineers proudly held the keys to the future in their hands… unaware that a similar fate would soon befall them.” Oops.

I doubt anyone here has a moral objection to GD if it’s on their own terms. Too bad we were all dragged into an adversarial discussion triggered by possibly the worst sales pitch on the planet. Despite being 5 years behind (whatever), I was looking forward to seeing some uploads from ID-ers. Wish I had some to share. I could symbol-spray something in Illustrator and have it laser-cut. Does that count?

http://www.stefandickerson.com

I never got the impression in this thread that any of the Designers see GD as a bad TOOL. The panacea that SK seems to think it is is the problem.

The birds nest analogy makes me think of the AutoRoute feature in PCB layout software. AutoRoute software was touted as a panacea-type tool when it first came out. That it was going to revolutionize the industry. The reality is that the PC isn’t able to route the nuances required within the context of a specific design. Routing the traces for a highly integrated handset is VERY product specific.

GD is just another Artificial Intelligence tool. Nothing more, nothing less. Give GD 100 yrs…maybe more, maybe less…when the AI algorithyms can truly go through high speed deductive reasoning with contextual analysis…then we can talk about it being a TOOL that can revolutionize an industry. Until then, it is a TOOL that I may consider.

Knowing what I do about parametric CAD…the amount of time to set up a GD model to truly create an “endless” amount of iterations simply doesn’t make sense to me. I would need to spend a minimum of a week to make sure all the dimensions are correct, the top down structure flows properly.

And the kicker is that is JUST ONE STYLE VARIATION.

I see the potential of this tool in the hands of a skilled designer.

Like Yo, I’d like to hear SK put this in the context of his experience with the tool in a real world scenario. A white paper. A case study, with real world numbers, and real worlds examples of success.

Until we get that, SK, you sound like a cheap car salesman.

Keeping the context of the discussion, but changing my approach to the constructive. When designing for a new area, an area which I do not have first hand knowledge or experience, I have to place complete faith in the people that are using the product (or process) to design them a better one. I also think it is important to personally use whatever I am designing. (This holds true for electric bikes, electric skateboards, backpacks, wake surfing boats, fitness equipment, pilates stations, all of which I have been required to generate ideas for in the past two years.) This also holds true for software tools. I first of all, listen to the expectations of the users, ask questions why things are done a certain way, get an idea of what can be changed and what is to remain fixed. There is a limited amount of elasticity in any product or process at any given time. The bounds.

If skilled designers were to actually design this tool, how would it function? What would be the brief? The question which people here have touched on. Designers, what could inspire you in your daily creative process for the items you design?

Since here we have a discussion forum by practicing designers of different backgrounds of experience, it seems a good place to ask the question.

What I personally would find inspiring as a resource:

Loose presentations of arrangements, sketches that were personally generated for me. I like the appearance of hand sketches. Therefore, I would like the rendering of the lines to be simulated pencil on paper or simulated ball point pen. Loosely rendered so I can personally interpret them in different ways. Perhaps with the ability to click on them and see a gray shaded view and print it out to sketch over.

Not too many, not in my face, maybe four or five on my web home page every morning at the top of the page like the google banner. Let me “vote” on the directions I like and don’t like, to make progress.

The sodaplay animation generators mentioned earlier in this thread are super cool. Give me an easy way to have variations of my structures generated to inspire me. My iTouch had a physics sandbox app that was simple and cool, 2d sketch and play, something similar would be nice.

Hide the fact that it is parametrized. I don’t want to think of my design in terms of parameters or math. Seriously, no numbers.

If I want to have some ideas inspired by automated generation, make it seem like magic.

That’s well observed; and, hopefully, the heat rises to such levels so as to melt that MGX “artificial intelligence stool” (or rather dustcatcher? flytrap? rocking-radiator?) thankfully posted earlier, because these objects and their collateral marketing bedlam pinpoint once again what occurs when software-fuelled can-do-ism goes to bed with unsustainable plastics rapid prototyping: precipitate delivery and parascientific afterbirth.

Much can be said in favour of augmenting whatever design process with algorithmic form-finding and morphology creation, but it’s equally good to keep in mind, that “[…] the double helix of DNA itself has become an enduring motif expressive of the machinery of life in art, design, illustration, and figurative speech. […] Such work sometimes seems so at odds with other trends in design aesthetics that one wonders whether it would ever have taken this form but for the gloss of scientific validity. […] Using science for inspiration is all well and good, but caution is necessary if larger claims are made for it. […] Critic Charles Jencks is thus misled when he answers his own question, ‘Why should one look to the new sciences for a lead?’ with these words: ‘Partly because they are leading in a better direction – towards a more creative world view than that of Modernism – and partly because they are true.’ Both of these justifications seek to endow design that is inspired by science with a superior moral authority. But garden ironwork such as Jencks himself has created inspired by ‘quantum waves’ has no higher morality or deeper meaning than a cornstalk fence. Designs with randomized elements chosen on the basis of DNA sequences – a recent fashion in architecture schools – have no closer connection to life as a result. These phenomena are as good a basis for a stylistic idea as any, but no better.” (Aldersey-Williams, Hugh, “Applied Curiosity” in Design and the Elastic Mind, The Museum of Modern Art, New York, 2008, p. 54)

I think it might be appropriate to allow Hugh Aldersey-Williams to finish his point. He also wrote in the next section:

“Like Gulliver, we return from Lilliput and Brobdinang only to find that some of the strangest goings-on are happening at the human scale. There is a case to be made that, for all their unanswered questions, it is the very large and the very small that are best understood by science. The middle of the range, the mesoscale, offers plenty of mysteries yet.

…The mesocale is where matter and energy behave in the ways intuitively familiar to us, where visualization is most relevant, and therefore where it is most likely that designers have a real contribution to make.

…All of biology happens at this scale.

…If tissue cells can be cultured to emulate human parts for use in reconstructive surgery, some designers have reasoned, then they can aslo be made to follow entirely novel forms.

…It is altogether harder, in these early days, to produce a thing of beauty.

…Other designers are taking their ideas from nature but executing them in artificial materials. Here is where nanotechnology and biosciences - apparently so different both in scale and in what one might call their romance - actually overlap.

…Such objects are evidence of a shift away from the machine and toward organism as cultural metaphor.

…One of design’s greatest problems, often ignored completely, is that of matching a product to its use not in the physical three dimensions of space, but over time.

…In nature, this problem is deviously solved by death: an organism dies once it ceases to have a use and ceases to have a use after it dies. A prime goal for designers now has to be to bring their objects’ material existence and practical utility into similar harmony. One might counter that nature is wasteful in its own way, cruelly redundant in its overproduction of species that merely become another species’ prey. But this is only wasteful from the species’ point of view: Nature’s concern is for the most economical management of the overall system. A comprehensive biomimetic design philosophy will require systems thinking a mile away from the designer’s traditional focus on the object.
This approach to design seeks to adapt specific advantages observed in natural organisms into human technology, but the polemical subtext of any design inspired by nature is that we are in danger of losing touch with the natural world. It’s pleads for the biological, the technological, and the ethical to come together. This is the objective of “consilience,” the term coined by biologist Edward O. Wilson for the reunification of the strands of intellectual inquiry artificially separated as a consequence of the growth of specialized disciplines in science and the humanities. In his book, ‘Consilience: The Unity of Knowledge’, Wilson writes: “If the world really works in a way so as to encourage the consilience of knowledge, I believe the enterprise of culture will eventually fall out into science, by which I mean the natural sciences, and the humanities, particularly the creative arts.”
Charles Eames and Richard Feynman were consilient personalities, but their meeting never happened because the world didn’t work in the right way. The question is: Does it now?”

Sure. Christina Cogdell’s review doi:10.1162/desi.2009.25.3.92 of that celebratory scientism-roadshow (a critique of its sloppy curation, not the accompanying catalogue texts) frames the problem rather nicely, as well as Massimo Negrotti’s thoughtful concerns doi:10.1162/desi.2008.24.4.26 regarding bold claims being made by just too many algorithmic can-do-ists purporting to be designing like nature - which in fact they aren’t. Back to that MGX contraption: no, osseous tissue does not mineralise that way; no, it is not the best morphologic exemplar to model flexibility whilst minimising material usage - it’s just a contemporary design emission, thinly coated with what Aldersey-Williams dubbed “the gloss of scientific validity”.

Perhaps you might think I’d be insulted by you calling someone else’s morphologic attempt an emissive contraption. You might also think that you can use whatever quotes you like out of context while arguing against the, “gloss of scientific validity”. That’s actually kind of entertaining. I’d prefer it if you had something constructive to add to the argument. I’ve read Design Issues, but there might be folks on here who aren’t willing to pay $60 to figure out why you’re brilliant and a whole slough of designers are mere can-do-ist twits. It has been mentioned numerous times in this thread, that good examples or methods are what we would all like to see. Now that you’ve successfully annihilated the MGX stool, perhaps you would like to install a better example in its place. We’re all pretty educated as to why design can’t hold a candle to nature, and we’re all about dismantling glossy facades. However, there’s a lot of info out there, and I for one would like to sift through it in a civil and educated manner. So pretty please, with sugar on top, let this thread die, or actually contribute something to the equation other than a sign change.

Oops, well, my comment here was surely not offensive, self-acclamatory or self-congratulatory as you suggest it was; but opinionated surely, as without personal opinions there’d be no debate :wink:

Design Issues and other design related publications are available through quite a few libraries actually; whether you’re a student or a professional, the subscription fee is fairly low, just about two to four high-street non-matinee movie tickets http://mitpress.mit.edu/journals/order/default.asp?issn=0747-9360

As far as algorithmic morphology generation goes, I can’t help but critique this particular example that was thankfully posted here earlier, because it is a good exemplar for what happens when, as Hugh A-W writes - also in this intriguing book on architecture http://www.hughalderseywilliams.com/html/books_zoomorphic.html - pseudo-scientific write-ups are used to paper over the cracks of can-do designs - for the gloss of scientific validity.

Also, I believe that particularly plastics rapid prototyping, as promoted through ever so many algorithmic creation websites and blogs, is no panacea - see last year’s Wohlers Report http://wohlersassociates.com/ - and has many disadvantages in terms of economic, social and ecologic sustainability. I agree most happily that working manufacturable examples are indeed scarce and my point is that can-do-ism won’t help to alleviate that situation. But then, possibly, this may change as many non-profit and academic institutions are disseminating their knowledge, paving the way for us practicing designers and design educators to augment our design processes with useful algorithmic nature and mathematics derived means of form-finding…

Thank you Feynman. I apologize for my reaction. You have to understand that in this thread, opinion has gotten us nowhere. And I have spent my summer reading mostly architectural publications in order to build some kind of reference for myself:

Thank you for the links, I’ll be sure to read them all. As for the debate, I doubt that there can be one if we aren’t properly educated or experienced.

1 Like

No problem - opinions, wittycisms, disagreements are what brings us all forward, although maybe not in this thread indeed. I’m practising and teaching the subject, so I pretty much enjoy professional or academic punch-ups :wink:

I’d just like to add that the paper below should be a must-read for all those interested in seriously engaging in the use of algorithms for the designing of objects - it’s well worth trying to get access to. 10 pages of excellent observations - and an entertaining read, too:

Ostwald, M. (2010). Ethics and the auto-generative design process. Building Research & Information, 38(4), 390-400. 10.1080/09613218.2010.481172

A short excerpt should be allowed:

“[…] Motivation, the final category for investigating the ethics of the design process, is closely related to issues of both transparency and authorship. While a lack of transparency may be an ethical flaw because it undermines the educative potential of a work (Orr, 1999), more commonly it is problematic because it is a result of a designer’s attempt to seek authority through analogy or by association (Ostwald, 1999). Similarly, while the tactic of hiding the role of the architect in the auto-generative process is possibly an ethical deficiency because it suggests a desire to avoid responsibly, it may equally relate to the attempt unduly to enhance the designer’s reputation. In both instances, the ethical flaw can be traced to the motivation of the architect. In this section, two examples are used to explore this idea.

In 2006, architects Achim Menges and Michael Hensel offered a description of a design exercise wherein:

[e]volutionary computation is used to initiate a process that coevolves different generations of two interlocking surfaces through perpendicular or tangential sections. The morphogenetic process yields an ever-increasingly complexity of the two coevolved surfaces that nevertheless remains coherent through the logics of the material system and the manufacturing [process].

This description, itself a microcosm of the definition of the auto-generative process,8 could equally have been reframed as follows:
We used computer-modelling software to experiment with two overlapping organic shapes until we were happy with the result. We then used a different piece of software to select the optimal cutting schedule for the material thickness required by the manufacturing process.

Both accounts are essentially the same. Admittedly, for one well versed in morphogenetic processes and the realities of computer-aided manufacturing, the first description contains marginally more information, but it is also heavily coded. The second description is only slightly less informative at a technical level, but it is more transparent in terms of both the actual process and its authorship. Significantly, the first description appears not only to emphasize the complexity of the process, but also it seems to exaggerate this complexity at every turn.
Terzidis (2006) is highly critical of the auto-generative design process for its propensity for falsely emphasizing complexity and thereby suggesting a high level of design sophistication. Terzidis observes that while the:

objective or result of an [algorithmic design process] may be complex, the strategy itself does not necessarily follow that complexity. In mathematics, it is common practice that a simple formula generates extremely complex outputs. For instance chaos [theory] itself is a study of how simple systems can generate complicated behaviour.

The problem with many descriptions of auto-generative design is precisely that they dwell on how supposedly complex the process is, while in reality all the hard work has been done by the software and the remainder is not complex at all.

Terzidis argues that most recursive, stochastic, emergent and evolutionary design strategies rely on ‘simple means’ (p. 118) to produce intricate forms. The real complexity in the auto-generative design process has been resolved by the software engineers responsible for authoring the program (Ostwald, 2006). This implied criticism is also apparent in Mark Burry’s thoughts on the true position of creativity in auto-generative design. For Burry (2001), the question is should such:

designers produce their own algorithmic self-learning tools, […] or is it a perfectly reasonable proposition for the designer to rely on the algorithms that come with the various software packages? John Ruskin’s view of artists needing to grind their own colors in the preparation of paint has some contemporary relevance here.

In the final example in this section, Lynn’s portrayal of the design process for the House in Long Island provides an example of seeking authority through analogy […]”.

Some introductory literature on the topic:

Agkathidis, A., Hudert, M. & Schillig, G. (2009). Form defining strategies: Experimental architectural design. Tübingen, Germany: Ernst Wasmuth Verlag GmbH & Co.

Aranda, B. & Lasch, C. (2005). Pamphlet architecture 27: Tooling. New York, NY: Princeton Architectural Press.

Attaway, S. (2009). Matlab: A practical introduction to programming and problem solving. Burlington, MA: Butterworth-Heinemann.

Bohnacker, H., Groß, B. & Laub, J. (2009). Generative Gestaltung: Entwerfen. Programmieren. Visualisieren. Mit internationalen best-practise-Beispielen, Grundlagen, Programmcodes und Ergebnissen. Mainz, Germany: Verlag Hermann Schmidt Mainz GmbH & Co. KG.

Hensel, M. & Menges, A. (Eds.). (2008). Versatility and vicissitude: Performance in morpho-ecological design (Architectural Design). Hoboken, NJ: John Wiley & Sons, Inc.

Hensel, M., Menges, A. & Weinstock, M. (Eds.). (2006). Techniques and technologies in morphogenetic design (Architectural Design). Hoboken, NJ: John Wiley & Sons, Inc.

Iwamoto, L. (2009). Digital fabrications: Architectural and material techniques. New York, NY: Princeton Architectural Press.

Kolarevic, B. (Ed.). (2005). Architecture in the digital age. Oxford, UK: Taylor & Francis Group.

Kolarevic, B. & Klinger, K. (2008). Manufacturing material effects: Rethinking design and making in architecture. New York, NY: Routledge.

Lally, S. (Ed.). (2009). Energies: New material boundaries (Architectural Design). Hoboken, NJ: John Wiley & Sons, Inc.

Meredith, M., Aranda, B., Lasch, C. & Sasaki, M. (Eds.). (2008). From control to design: Parametric/algorithmic architecture. Barcelona, Spain: Actar.

Noble, J. (2009). Programming interactivity: A designer’s guide to Processing, Arduino, and Openframeworks. Sebastopol, CA: O’Reilly Media, Inc.

Pearce, P. (1980). Structure in Nature is a Strategy for Design. Cambridge, MA: The MIT Press.

Sachs, A. (Ed.). (2007). Nature design: From inspiration to innovation. Baden, Switzerland: Lars Müller Publishers GmbH.

Terzidis, K. (2006). Algorithmic architecture. Oxford, UK: Architectural Press.

Williams, R. (1979). The geometrical foundation of natural structure: A source book of design. New York, NY: Dover Publications, Inc. (Original work published 1972).

Some background literature, related to the topic, debating…

…why genetic design will always be more sustainable than mimetic design.
Ackrill, J. & Judson, L. (Eds.). (2002). Aristotle: On the parts of animals I-IV (J. Lennox, Trans.). Oxford, UK: Oxford University Press.

…why humans are predisposed to invent, design and produce new objects and culture.
Baudrillard, J. (2006). The system of objects (J. Benedict, Trans.). London, UK: Verso. (Original work published 1968).

…why the superficial might be winning over substance in commodified societies.
Debord, G. (1995). The society of the spectacle (D. Nicholson-Smith, Trans.). New York, USA: Zone Books. (Original work published 1967).

…why there may be no such thing as “the scientific method”.
Feyerabend, P. (2010). Against method (4th ed.). London, UK: Verso.

…why scientific findings and truths are rather temporary sociological constructs.
Fleck, L. (1981). Genesis and development of a scientific fact (F. Bradley, Trans.). Chicago, USA: The University of Chicago Press. (Original work published 1935).

…why everything is design and design is devoid of meaning.
Flusser, V. (1999). The Shape of things: A philosophy of design. London, UK: Reaktion Books Ltd.

…why there is such thing as ecology (Haeckel coined that term).
Haeckel, E. (1866). Generelle morphologie der organismen. Allgemeine grundzüge der organischen formen-wissenschaft, mechanisch begründet durch die von Charles Darwin reformirte descendenztheorie. Berlin, Germany: Verlag von Georg Reimer.

…why Langdon Winner’s idea that societies and behaviour can be changed by design is wrong.
Joerges, B. (1999). Do politics have artefacts? Social Studies of Science, 29, 411-431.
doi:10.1177/030631299029003004.

…why, since the Renaissance, art and science have always enjoyed a necessary relationship.
Kemp, M. (2006). Seen/unseen: Art, science, and intuition from Leonardo to the Hubble Telescope. Oxford, UK: Oxford University Press.

…why resisting the new cannot hinder the emergence of paradigm shifts (Kuhn coined that term).
Kuhn, T. (1996). The Structure of Scientific Revolutions (3rd ed.). Chicago, USA: The University of Chicago Press.

…why more and more consumers want to co-create and participate and how that changes economy.
Mugge, R. (2008). Emotional bonding with products: Investigating product attachment from a design perspective. Saarbrücken, Germany: VDM Verlag.

…why there is actually no such thing as technological determinism and “progress”.
Nye, D. (2006). Technology matters: Questions to live with. Cambridge, USA: The MIT Press.

…why Renaissance artists from Alberti to Leonardo happily embraced mathematics.
Panofsky, E. (2005). The Life and Art of Albrecht Dürer. Princeton, NJ: Princeton University Press. (Original work published 1943).

…why a genetic approach to designing is justified, as the end of evolution will remain unknown.
Ruprich-Robert, V. (1876). Flore ornementale, essai sur la composition de l’ornement, éléments tirés de la nature et principes de leur application. Paris, France: Dunod.

…why all nature is the result of invisible forces and that superior performance justifies complexity.
Thompson, D. W. (1992). On growth and form. New York, USA: Dover Publications. (Original work published 1942).

Feynman,

Great reading list, I especially enjoy your inclusion of Verso publications like Baudrillard’s, ‘The System of Objects’. I don’t know many people who enjoyed that book (although admittedly I did). Are there any works by Gilles Deleuze that might make the list as well?

I am also curious as to a book by Robert Woodbury that will be published this summer:

I guess it’s pointless to ask about something that hasn’t been published yet, but I thought you might possibly been privy to an advance copy for educational purposes?

Good afternoon lyfk,

well, the book is out, but I’d be reluctant to buy it, because Robert Woodbury’s teaching is quite heavily centered on Bentley Systems, Inc. Generative Components which surely is a well working and exciting tool but maybe not so ideally suited for product designers. I’d be cautious when books come with marketing blurb as this “[…] Pushed by practices wanting and needing to produce novelty […]” and a content page as this “1. Introduction 2. What is Parametric Modeling? 3. How Designers Work 4. Programming 5. The New Elephant House, Copenhagen 6. Geometry 7. Onur Gun 8. Patterns for Parametric Design 9. Hysterical Space” where, in my opinion, Buro Happold’s and Foster + Partners’ tessellated British Museum Great Court roof would have been an example with a much higher architectonic quality. But, have a look at his teaching experience and especially the projects undertaken here School of Interactive Arts & Technology - Simon Fraser University to judge for yourself, if this is really a book you should invest in.

Baudrillard is a good reference because, apart from his texts on humans and their relation to the artificial, his writing is not clouding meaning with vainglorious meanderings as Deleuze, Lacan and other postmodernists who, for a while, posed as architecture and design critics. And, that is why Ostwald’s Ethics and the auto-generative design process is such a sobering and refreshing read…

ps: Some more (very) introductory literature on the topic:

Antonelli, P. (Ed.). (2008). Design and the elastic mind. New York, NY: The Museum of Modern Art, New York.

Knauer, R. (2008). Transformation: Basic principles and methodology of design. Basel, Switzerland: Birkhäuser Verlag AG

Maybe we can bring this topic back to life after 7 years. I have seen a lot of requests for generative design assignments and projects, from surface textures to lighting installations, with also big companies such as Philips now recruiting for generative design talents. I am wondering if anyone else notices this too and focusing in this area. I think there is a big future for generative design, and a huge opportunity for the first software that can combine generative design, genetic algorithms and A-class surfacing.

A good book by the way is Textile Tectonics by Lars Spuybroek since it relates generative design to the history of building cathedrals which is comparable.

a lot of designers are using Grasshopper for that kid of surface texture iteration

It is interesting and also somewhat scary for this to resurface at this moment. I have been accepted to do a PhD on the subject starting in July.
Realistically I think it will result in furniture based products with some fancy sliders for customers to specify their products. The difference is it will be customer driven and specified, not designing 1000s of options for the designer to choose from.
I used to use the term Parametric Design but realistically Computational Design is a more appropriate term for what I want to do. I would avoid Generative Design due to Autodesks taking over of the term which means something different to them.