Looking in Amazon, they have the book, but I haven't been able to find the quote there, possibly because it appears to be a later edition than what I read. However, I did find the following (note that I didn't copy everything, since I had to do so by hand - no copy-paste - but you can find the text in the Amazon link):
Dayan's 1976 comments on Israel's behavior were rather sweeping and simplistic. They may have been colored by his disgrace and resignation as defense minister following his failure to anticipate the Arab attack in October 1973. This failure thrust him into the political wilderness and led him to question the offficial Israeli version of the conflict. Being a man of extremes, he now exonerated the Syrians and placed most of the blame for the conflict on the Israeli side.
I should note here that Dayan is remembered for many things - honesty isn't really one of them.
although Dayan gor most of the glory for the victory over Syria, he himself later regarded the decision to go to war against Syria as a mistake. In his 1976 conversations with the journalst Rami Tal, Dayan confessed that on the fourth day of the June war he had failed in his duty as minister of defense by agreeing to the war with Syria. There really was no pressing reason to go to war with Syria, he said*. The kibbutz residents who pressed the government to take the golan Heights did so less for security than for the farmland. Dayan admitted that these civilians had suffered a lot. "But I can tell you with absolute confidence, the delegation that came to pursuade Eshkol to take the heights was not thinking of these things. They were thinking about the height's land". This confidence was unjustified. The protocol of the meeting of the ministerial defense committee show the kibbitz leaders spoke only about the nightmarish security situation and made no mention of land.
The allegation that Israel went to war against Syria because the kibbutz residents coveted Syrian land provoked strong indignation in Israel. There was even greater anger at Dayan's allegations from the grave that Israel's security situation was not threatened by the Syrians...Dayan's various accounts of the reasons for the war against Syria are so allarmingly inconsistent that one needs to be a psychologist to fathom his behavior. But one thing emerges clearly from all his contradictory accounts: the Eshkol government did not have a political plan for the war....The one thing it** did not have was a master plan for territorial aggrandizement.
*A few pages before, Shlaim describes how Dayan, during the war, cited security concerns as a reason to attack the Golan, even further than was planned at the time.
**Israel (anyone know how I can get brackets to show?)
And again, there's still the phsyical evidence I described above to consider.