The concept of the atom, proposed 24 centuries ago and rejected by Aristotle, was born on a purely philosophical basis, surely without anticipating some of the 20th century's most triumphant scientific discoveries. Atoms can now be seen, observed in motion, and manipulated...

Freezing Time – In a Femtosecond, Sci. Spectra 14, 62 (1998).

With ultrashort pulses of laser light, it has become possible to observe physical, chemical and biological changes with a resolution of femtoseconds, 15 orders of magnitude faster than the human heart beat, reaching the scale of atomic motion, spatial and temporal...

The Birth of Molecules, Sci. Am. 263, 76 (1990).

In 1872 railroad magnate Leland Stanford wagered $25,000 that a galloping horse, at some point in stride, lifts all four hooves off the ground. To prove it, Stanford employed English photographer Eadweard Muybridge. After many attempts, Muybridge developed a camera shutter that opened and closed for only two thousandths of a second, enabling him to capture on film a horse flying through the air. During the past century, all scientific disciplines from astrophysics to zoology have exploited high-speed photography to revolutionize understanding of animal and mechanical motions that are quicker than the eye can follow...

Ultrafast Reaction Dynamics, Phys. Today 43, 24 (1990).

With new laser techniques and with gas phase and molecular beam experiments, it is now possible to determine the ultrafast motion in isolated chemical reactions: chemistry on the 10^-13-second time scale...

Laser Selective Chemistry: Is It Possible?, Phys. Today 33, 27 (1980).

With sufficiently brief and intense radiation, properly tuned to specific resonances, we may be able to fulfill a chemist's dream, to break particular selected bonds in large molecules...