It seems you are interpreting what is said in black and white terms. He (she?) said that personality is _neither_ completely _fixed_ _nor_ completely _mutable_. Things are not either/XOR.
The same goes with IQ. I don't think any average person could ever train their intelligence to be, say, John von Neumann. Thus it is not _completely_ mutable. He was a genetically superior specimen by every account and evidenced such from a very young age. But a good 15-20 point boost, especially if we did not train ourselves to our fullest before? Maybe. I used to process more slowly, now I process faster, because I pushed to think quicker. Thus it is not completely _fixed_, either. Definitely we can eradicate racial IQ gaps, I believe (average Black-White IQ gap in the US is 15 points favoring Whites, by the way.), Rushton et. al. be damned. If I remember right, in some places it was actually done, thus proving its possibility. (Interesting tidbit the racists seem not to address: Bhutan's and China's people are both “Mongoloid Asian" race by racist theory – but Bhutan has IQ 85, China at 105, at least using racists' own data sets. I wonder also what the IQ for rural China vs. urban wealthy China looks like. I suspect the 105 number comes from having a large proportion of the latter in the sample.)
The same goes with IQ. I don't think any average person could ever train their intelligence to be, say, John von Neumann. Thus it is not _completely_ mutable. He was a genetically superior specimen by every account and evidenced such from a very young age. But a good 15-20 point boost, especially if we did not train ourselves to our fullest before? Maybe. I used to process more slowly, now I process faster, because I pushed to think quicker. Thus it is not completely _fixed_, either. Definitely we can eradicate racial IQ gaps, I believe (average Black-White IQ gap in the US is 15 points favoring Whites, by the way.), Rushton et. al. be damned. If I remember right, in some places it was actually done, thus proving its possibility. (Interesting tidbit the racists seem not to address: Bhutan's and China's people are both “Mongoloid Asian" race by racist theory – but Bhutan has IQ 85, China at 105, at least using racists' own data sets. I wonder also what the IQ for rural China vs. urban wealthy China looks like. I suspect the 105 number comes from having a large proportion of the latter in the sample.)