A physical law must possess mathematical beauty - Paul Dirac

People who equate all the different kinds of human activity to money are taking too primitive a view of things.

My research work was based in pictures. I needed to visualise things and projective geometry was often most useful e.g. in figuring out how a particular quantity transforms under Lorentz transf[ormation]. When I came to publish the results I suppressed the projective geometry as the results could be expressed more concisely in analytic form.

<math>{\int _{-\infty }^{\infty }{\delta \left({x}\right){d{x}}}}=1</math>
<math>\delta \left({x}\right)=0 \text{ for } x\not= 0</math>