A Finnish Professor would raise inheritance tax up to 65 percent

Professor Heikki Hiilamo of the Helsinki University proposed that inheritance tax should be raised up to 65 percent. He justified that by the inequality of people, which reduces the chances of poor people to succeed in the society. He also noted that it takes a lot of education to allow them a chance to prosper, which is expensive and not possible in a highly unequal society. 

I just wonder how would such a high taxation of inheritance affect the motivation of elder people to work - and pay taxes - when their offspring would inherit only a third of their fortune and property? And how would that affect the accumulation of funds for investments in private companies owned by single families? 

And ultimately, how would such a high taxation finally affect the living standard of poor people in a free world, where rich ones always have a chance to find a new home in a country, where the taxation is reasonable and hard working is encouraged by a possibility of transferring its outcome to offspring?

Previous thoughts on the same topic:
International Master´s degree is an opportunity to be used
A nurse´s question: who deserves health care, and who does not
Misuse of taxpayers´ money in Finland