Lila mentions cancer, which I think is very instructive in this context. A “war on cancer” was declared about 45 years ago. Since then, 100-300 billion dollars have been spent on cancer R&D. Very little progress has been made. Why should we expect a SENS-inspired “war on aging” to make lots of progress, on all sevencauses of aging (of which cancer is just one), in one third of that time, with one hundredth of that budget?
EDIT: The paragraph above overstretches the analogy bewteen cancer and aging. See Gwern’s comment below.
Saying ‘very little progress’ seems to considerably understate it; many cancers are now treatable which were untreatable, and even former death sentences can be cured. As well, much of that research was spent in the past on expensive but obsolete methods or on building knowledge bases and tools which are now available for anti-aging research. (While Apollo may have cost $26b to put a man on the moon in 1969, it should not then cost another $26b in 2017 to put another man on the moon.)
Comparing with cancer is interesting in part because they’re so different. Cancer is a hostile self-reproducing ecosystem which literally evolves as it is treated; aging and senescent cells, however, appear to be none of those. For example, it appears to be a lot easier to trick a senescent cell30246-5 “‘Targeted Apoptosis of Senescent Cells Restores Tissue Homeostasis in Response to Chemotoxicity and Aging’, Baar et al 2017”) into committing suicide than a cancer cell.
Why should we expect a SENS-inspired “war on aging” to make lots of progress, on all seven causes of aging
Do you really need progress on all 7? Mortality with age follows a Gompertz distribution which has an exponential term increasing mortality risk and a baseline hazard/risk; interventions on the aging process itself, as opposed to tinkering with improved fixes for symptoms like cancer, would seem like they would affect the exponential term and not the hazard term. Since the Gompertz mortality curve is dominated by the exponential term, not the baseline hazard ratio, even small reductions in the aging rate lead to large changes in life expectancy. (In contrast, large reductions in the hazard ratio, like halving, only add a few years.)
Lila mentions cancer, which I think is very instructive in this context. A “war on cancer” was declared about 45 years ago. Since then, 100-300 billion dollars have been spent on cancer R&D. Very little progress has been made. Why should we expect a SENS-inspired “war on aging” to make lots of progress, on all seven causes of aging (of which cancer is just one), in one third of that time, with one hundredth of that budget?
EDIT: The paragraph above overstretches the analogy bewteen cancer and aging. See Gwern’s comment below.
Saying ‘very little progress’ seems to considerably understate it; many cancers are now treatable which were untreatable, and even former death sentences can be cured. As well, much of that research was spent in the past on expensive but obsolete methods or on building knowledge bases and tools which are now available for anti-aging research. (While Apollo may have cost $26b to put a man on the moon in 1969, it should not then cost another $26b in 2017 to put another man on the moon.)
Comparing with cancer is interesting in part because they’re so different. Cancer is a hostile self-reproducing ecosystem which literally evolves as it is treated; aging and senescent cells, however, appear to be none of those. For example, it appears to be a lot easier to trick a senescent cell30246-5 “‘Targeted Apoptosis of Senescent Cells Restores Tissue Homeostasis in Response to Chemotoxicity and Aging’, Baar et al 2017”) into committing suicide than a cancer cell.
Do you really need progress on all 7? Mortality with age follows a Gompertz distribution which has an exponential term increasing mortality risk and a baseline hazard/risk; interventions on the aging process itself, as opposed to tinkering with improved fixes for symptoms like cancer, would seem like they would affect the exponential term and not the hazard term. Since the Gompertz mortality curve is dominated by the exponential term, not the baseline hazard ratio, even small reductions in the aging rate lead to large changes in life expectancy. (In contrast, large reductions in the hazard ratio, like halving, only add a few years.)