Peter Lipton

"What truth is not, according to Kuhn, is an accurate representation of the world as it is in itself. Scientific theories represent a world, but one partially constituted by the cognitive activities of the scientists themselves. This is not a commonsensical view, but it has a distinguished philosophical pedigree, associated most strongly with Kant. The Kantian view is that the truths we can know are truths about a ‘phenomenal’ world that is the joint product of the ‘things in themselves’ and the organising, conceptual activity of the human mind. Kuhn, however, is Kant on wheels. Where Kant held that the human contribution to the phenomenal world is invariant, Kuhn’s view is that it changes fundamentally across a scientific revolution. This is what he means by his notorious statement that, after a scientific revolution, ‘the world changes’. This is neither the trivial claim that scientists’ beliefs about the world change, nor the crazy claim that scientists can change the things in themselves simply by changing their beliefs. It is the claim that the phenomenal world changes because the human contribution to it changes."

"For Kuhn, scientific development is neither cumulative nor teleological: science is not moving towards the goal of a theory of everything. His favoured analogy is with biological evolution by natural selection. Organisms develop under selective pressures from the environment, but development, though tending to an increase in complexity and differentiation, has no fixed goal. Moreover, the selective environments that determine which organisms survive and which die off themselves change and are partially constituted by the organisms’ own activities. Biological evolution is not moving towards an ideal organism, and scientific evolution is not moving towards the Truth. Both processes are pushed from behind, not pulled from the front."

"Students in the Department would often attempt to help one another by ‘Liptonating’ (or ‘Liptonising’): expressing the content of one’s interlocutor’s garbled thoughts in far superior terms of clarity, precision, and concision."

"His ability charitably to “summarise” the inchoate and/or confused thoughts of his interlocutors was legendary: Lipton invariably said what you wished you had meant."

"Lipton once gave me some advice that I like quite a lot: if a footnote says something important, put it in the main text where people will read it. If it says nothing important, delete it."