Rudolf Clausius
Heat can never pass from a colder to a warmer body without some other change, connected therewith, occurring at the same time.Collection: Body
The total energy of the universe is constant; the total entropy is continually increasing.Collection: Energy
The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.Collection: Increase
The energy of the universe is constant.Collection: Energy
The algebraic sum of all the transformations occurring in a cyclical process can only be positive, or, as an extreme case, equal to nothing. Statement of the second law of thermodynamics, 1862Collection: Law
The entropy of the universe tends to a maximum.Collection: Entropy
In all cases where work is produced by heat, a quantity of heat proportional to the work done is expended; and inversely, by the expenditure of a like quantity of work, the same amount of heat may be produced.Collection: Done