The purpose of the "bootstrap program" is to construct integrable quantum
field theories in 1+1 dimensions in terms of their Wightman functions
explicitly. As an input the integrability and general assumptions of local
quantum field theories are used. The object is to be achieved in tree steps: 1)
The S-matrix is obtained using a qualitative knowledge of the particle spectrum
and the Yang-Baxter equations. 2) Matrix elements of local operators are
calculated by means of the "form factor program" using the S-matrix as an
input. 3) The Wightman functions are calculated by taking sums over
intermediate states. The first step has been performed for a large number of
models and also the second one for several models. The third step is unsolved
up to now. Here the program is illustrated in terms of the sine-Gordon model
alias the massive Thirring model. Exploiting the "off-shell" Bethe Ansatz we
propose general formulae for form factors. For example the n-particle matrix
element for all higher currents are given and in particular all eigenvalues of
the higher conserved charges are calculated. Furthermore quantum operator
equations are obtained in terms of their matrix elements, in particular the
quantum sine-Gordon field equation. Exact expressions for the finite wave
function and mass renormalization constants are calculated.Comment: Latex, 23 page