The "leading" Historian of Bulgaria, Bozhidar Dimitrov is always changing his mind about historical events, as long as it suits his needs. For example, in his book the 10 lies of the Macedonism, he writes:

"Историската наука одамна утврдила дека
античките македонци се племе, кое било дел
от грчката етничка заедница и чија територија
до 4 век пр. Хр. се наоѓала во денешна Северна
Грција."

Translation:

"The History science have concluded before long time that the Ancient Macedonians were a Greek tribe, and whose territory till the fourth Century BC was encompased in Modern North Greece."

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But the opinion of Bozhidar Dimitrov have evolved. In the Bulgarian news paper Standard from 13th August 2006, Bozhidar Dimitrov have changed the descend of the Ancient Macedonians in DISTINCT NATION who was RELATED to the Thracians and Illyrians, and whose Macedonian State was NEIGHBOR to Greece.

"Историческата наука отдавна е установила,
че античните македонци са племе, сродно на траките
и илирите. Царството им се намира в непосредствено
съседство с древна Еладa. ...Въпреки че според
нас място за спор няма - всеизвестно е, че дори на
Александър Велики е отказано да участва в Олимпийските
игри - макар и ученик на самия Аристотел, той не е грък."

Translation:

"The History science have concluded before long time that the Ancient Macedonians were a tribe, related to the Thracians and Illyrians. Their Kingdom was placed direct to the Ancient Hellas(Greece) ... So forus there are no doubts - it is apperant that that even Alexander the Great was refused to take part in the Olympic games - and though he was descipel of Aristoteles, he was not Greek."

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First of all, it seems that for Bozhidar Dimitrov the History science have for a long time concuded what the Ancient Macedonians were, even though it is something which he is not really certain of it what it really was. In one case he claims that one thing and than he claims the total oposite thing. But this does not prevent him of claiming that all this is already concluded by the History Science.