p Lenin analysed the above crisis in his book Materialism and Empirio-criticism and showed that it had arisen because natural scientists shared the views of the metaphysical materialists and explained the newest discoveries in physics accordingly. Indeed, the notion of matter as a totality of immutable atoms was upheld by metaphysical, not dialectical, materialism. The latter has never reduced matter to atoms, and never considered nor could consider them invariable and eternal. According to dialectical materialism, no concrete form pf thp pYistpti(;p of matter-atom, molecule or electron-is eternal and invariable On the contrary, it is constantly in motion and change, ’inflfir rrrtiin ffrnditiTT—turning—into other concrete forms, which themselves turn into ^ infimtum Engels wrote: ror it  [dialectical philosophy] nothing is final, 98 absolute, sacred. It reveals the transitory character of everything and in everything; nothing can endure before it except the uninterrupted process of becoming and of passing away. . .”.  [98•1 

p The discovery of the disintegration of the atom into other, smaller particles, as well as the transformation of matter into light, does not, therefore, refute dialectical materialism. On the contrary, it reaffirms the truth of its principles, such as that stating that everything existing in the world is in constant motion and changes from one thing into another.

p What, then, is matter as seen by dialectical materialism? The concept of matter is tied UP with all that exists outside and independently of the rmman mind, with the whole of objective reality. So, matter includes not only atoms, but also the “elementary” particles into which they disintegrate; not only substances, but also the light waves they emit under relevant conditions.

“Matter,” Lenin wrote, “is a philosophical category denoting the objective reality which is given to man by his sensations, and which is copied, photographed and reflected by our sensations, while existing independently of them.”  [98•2